As is well known and understood, a great many of the dusting powders (including baby and body powders, in general, on the market today) contain varying amounts of talc. It has also been publicized, however, that talc has been determined to be a potential cause of pulmonary disorder. At least in part because of this danger--and additionally the possibility that talc powders present an inhalation danger as well as a potential danger by virtue of their being able to be absorbed into the body via cracked, open skin--more and more manufacturers began to eliminate talc powders from their product lines. Talc has been replaced with other powders employing corn starch or rice starch. Those manufacturers using corn starch or rice starch, however, employ calcium phosphates (e.g. calcium triphosphate) as anti-caking and anti-clustering agents. The problem with these formulations is the fact that the calcium phosphates tend to be serious mucous membrane irritants--to the extent that when they are employed to keep the corn starch or rice starch from clustering, the manufacturer often carries a warning on the product label. It is recommended that these powder products be kept away from the face of a child being treated with the powder to minimize inhalation of the powder and the possible breathing difficulties which may result.
Thus, while the body powder manufacturers have succeeded at least to some extent in eliminating talc from the powder market, the alternative product incorporates deleterious agents by necessity, which have been suggested to be irritating and harmful to mucous membranes and the upper respiratory tract as well as the eyes and skin.
The initial investigation of liquid powder mixtures included micro-milling (below about 10 microns) polysaccaride particles such as starches in conjunction with alcohols and ethers. Starch in the above form is white powder, and the naked eye can detect little difference between the various starches extracted from different plants. Numerous percent composition mixtures were made ranging from 20-80% starch and 80-20% alcohol and/or ether, respectively. However, even though these mixtures provided the simple basis for a liquid powder product they were undesirable for a number of reasons, many of them related to the inadequacies of the delivery vehicle.
The above-described material compositions resulted in product deficiencies which brought about the need to investigate an alternative to the alcohols and ethers.
Organosilicones are not found in nature and must be prepared synthetically. The ultimate starting material is sand (silicon dioxide) or other inorganic silicates, which make up 75% of the Earth's crust. The organosilicones were first synthesized in 1863 by Friedel and Crafts, who first prepared tetraethylsilane. In the following years, although many other derivatives were synthesized, it was not until the 1940's that widespread interest in organosilicon chemistry emerged.
Silicon is a relatively electropositive element that forms polar covalent bonds with carbon and other elements, including the halogens, nitrogen and oxygen. The strength and reactivity of silicon depend on the relative electronegativity of the element to which the silicone will be covalently bound. The polysilanes upon controlled hydrolysis readily form the polysiloxanes. These cyclic and linear polymers are commercially known as silicones. The cylic siloxanes are used in the present invention as delivery vehicles for body powders to provide compositions with unique characteristics.